Optical element and preparation method thereof
Patent Information
- Application Number
- CN202310870275.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-07-14
- Publication Date
- 2025-01-14
AI Technical Summary
The internal stress caused by the difference in thermal expansion coefficients in high temperature environments between the metal film and the substrate can easily cause the metal film to rupture or detach from the substrate, affecting the durability of the optical components.
A metal connecting layer is introduced into the optical element, with a thermal expansion coefficient between the substrate and the metal layer, and a dielectric layer is formed on the metal layer to reduce internal stress and improve durability.
It effectively reduces the internal stress between the metal connecting layer, the substrate and the metal layer, avoids cracking or detachment, and improves the stability and durability of the optical components in high temperature environments.
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Figure CN119310658A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of optical elements, and in particular to optical elements and methods for preparing the same. Background Art
[0002] Metal films are widely used in the optical field because of their good optical properties such as reflectivity, polarization and extinction. In order to improve the optical properties of the substrate, the metal film is generally directly plated on the surface of the substrate by physical evaporation, magnetron sputtering or chemical vapor deposition. However, since the thermal expansion coefficient of the metal film and the thermal expansion coefficient of the substrate are usually very different, or even not in the same order of magnitude, it is very easy to generate large internal stress between the metal film and the substrate in a high temperature environment, such as during a temperature experiment, which can cause the metal film to rupture or detach from the substrate. Summary of the invention
[0003] The optical element and the method for manufacturing the same provided in the embodiments of the present application can solve or partially solve the above-mentioned deficiencies in the prior art or other deficiencies in the prior art.
[0004] The optical element according to the first embodiment of the present application includes:
[0005] Base material;
[0006] A metal connection layer covering the surface of the substrate; and
[0007] A metal layer covering the surface of the metal connection layer away from the substrate;
[0008] Wherein, the thermal expansion coefficient of the metal connection layer is between the thermal expansion coefficient of the substrate and the thermal expansion coefficient of the metal layer.
[0009] According to one embodiment of the present application, the thermal expansion coefficient k of the metal connection layer is o The thermal expansion coefficient k of the metal layer m Satisfies: 0.1≤k m / k o ≤10.
[0010] According to one embodiment of the present application, the thickness h of the metal connection layer is o , the thickness of the metal layer h m , the thermal expansion coefficient k of the metal connection layer o The thermal expansion coefficient k of the metal layer m Satisfy: (|lg(h m / h o )|) / (|ln(k m / k o )|)≤4.
[0011] According to one embodiment of the present application, the material of the metal connection layer includes at least one of nickel, zirconium, chromium and oxides thereof.
[0012] According to one embodiment of the present application, the surface tension σ of the metal connection layer o , the thermal expansion coefficient k of the metal connection layer o The thermal expansion coefficient k of the metal layer m Satisfies: (lgσ o ) / (|ln(k m / k o )|)≥1.1.
[0013] According to one embodiment of the present application, the material of the substrate is plastic, the optical element further includes a substrate connecting layer located between the substrate and the metal connecting layer, and the material of the substrate connecting layer includes a transition metal oxide.
[0014] According to an embodiment of the present application, the optical element further includes a dielectric layer, and the dielectric layer covers a surface of the metal layer away from the metal connecting layer.
[0015] According to an embodiment of the present application, the number of the dielectric layers is multiple, and the multiple dielectric layers are stacked sequentially on one side of the metal layer in a direction away from the metal layer, and materials of two adjacent dielectric layers are different.
[0016] According to an embodiment of the present application, two sides of at least one dielectric layer are respectively in contact with two other dielectric layers made of different materials.
[0017] According to an embodiment of the present application, the material of the dielectric layer includes at least one of aluminum oxide, silicon oxide, titanium oxide, niobium oxide, tantalum oxide and magnesium fluoride.
[0018] According to an embodiment of the present application, the material of the metal layer includes at least one of gold, copper and platinum.
[0019] The method for preparing an optical element according to the second aspect of the present application includes:
[0020] forming a metal connection layer on a surface of the substrate; and
[0021] forming a metal layer on a surface of the metal connecting layer away from the substrate;
[0022] Wherein, the thermal expansion coefficient of the metal connection layer is between the thermal expansion coefficient of the substrate and the thermal expansion coefficient of the metal layer.
[0023] According to one embodiment of the present application, forming a metal connection layer on the surface of a substrate includes:
[0024] placing the substrate into a vacuum coating chamber, and injecting oxygen into the vacuum coating chamber at a preset volume flow rate; and
[0025] The oxygen is ionized, and an electron gun is used to bombard the coating material in the vacuum coating chamber to form the metal connection layer on the surface of the substrate.
[0026] According to one embodiment of the present application, the preset volume flow rate is 0-200 sccm.
[0027] According to one embodiment of the present application, before forming the metal connection layer on the surface of the substrate, the preparation method further includes:
[0028] A substrate connection layer is formed on the surface of the substrate, and the material of the substrate connection layer includes a transition metal oxide.
[0029] According to an embodiment of the present application, the preparation method further includes: forming at least one dielectric layer on a surface of the metal layer away from the metal connection layer.
[0030] The optical element and the preparation method thereof provided in the embodiments of the present application can realize the transition of thermal expansion deformation between the substrate and the metal layer with the help of the metal connecting layer by arranging a metal connecting layer between the thermal expansion coefficient of the substrate and the thermal expansion coefficient of the metal layer between the substrate and the metal layer. In other words, the thermal expansion coefficient of the metal connecting layer is not much different from the thermal expansion coefficient of the substrate, and the thermal expansion coefficient of the metal connecting layer is not much different from the thermal expansion coefficient of the metal layer. Therefore, when the optical element is in a high temperature environment, no large internal stress will be generated between the metal connecting layer and the substrate, and between the metal connecting layer and the metal layer, thereby preventing the metal connecting layer and the metal layer from cracking or detaching from the substrate.
[0031] It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the present application, nor is it intended to limit the scope of the present application. Other features of the present application will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS
[0032] Other features, purposes and advantages of the present application will become more apparent by reading the detailed description of the non-limiting embodiments made with reference to the following drawings. The drawings are used to better understand the present solution and do not constitute a limitation of the present application. In the drawings:
[0033] Figure 1 is a schematic structural diagram of one optical element according to the present application;
[0034] Figure 2 is a schematic structural diagram of another optical element according to the present application;
[0035] Figure 3 is a schematic structural diagram of an optical element according to Example 1 of the present application;
[0036] Figure 4 is a schematic structural diagram of an optical element according to Example 2 of the present application;
[0037] Figure 5 is a schematic structural diagram of an optical element according to Example 3 of the present application; and
[0038] Figure 6 It is a schematic diagram of the process of preparing the optical element according to the present application.
[0039] Reference numerals:
[0040] 100, substrate; 200, substrate connection layer; 300, metal connection layer; 400, metal layer;
[0041] 500. Dielectric layer. DETAILED DESCRIPTION
[0042] In the description of the embodiments of the present application, it should be noted that the terms "longitudinal", "lateral", "upper", "lower", "top", "bottom", "inner", "outer", etc., indicating the orientation or state relationship, are based on the orientation or state relationship shown in the drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the embodiments of the present application. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.
[0043] In the description of the embodiments of the present application, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present application can be understood according to specific circumstances.
[0044] In the embodiments of the present application, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.
[0045] The following is a description of exemplary embodiments of the present application in conjunction with the accompanying drawings, including various details of the embodiments of the present application to facilitate understanding, which should be considered as merely exemplary. Therefore, it should be recognized by those of ordinary skill in the art that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present application. Similarly, for the sake of clarity and conciseness, the description of well-known functions and structures is omitted in the following description.
[0046] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.
[0047] Metal films are widely used in the field of optics because of their good optical properties such as reflectivity, polarization and extinction. Taking optical lenses as an example, optical lenses play an irreplaceable role in many fields such as smart phones, security monitoring, car assisted driving, intelligent detection and virtual reality. Optical lenses usually include a plurality of lenses arranged in sequence along the optical axis, and the more lenses there are, the lower the transmittance of the optical lens. In the related art, in order to improve the transmittance of the lens, a layer of metal film is usually coated on the surface of the lens. However, since the thermal expansion coefficient of the metal film is much larger or much smaller than the thermal expansion coefficient of the lens, or even not in the same order of magnitude, it is very easy to generate large internal stress between the metal film and the lens in a high temperature environment, such as during a temperature experiment, which may cause the metal film to rupture or detach from the lens.
[0048] like Figure 1 As shown, in order to at least solve the above problems, an embodiment of the present application provides an optical element, which includes a substrate 100, a metal connection layer 300 and a metal layer 400, wherein the metal connection layer 300 and the metal layer 400 are sequentially stacked on one side of the substrate 100, in other words, the metal connection layer 300 covers the surface of the substrate 100, and the metal layer 400 covers the surface of the metal connection layer 300 away from the substrate 100. The thermal expansion coefficient of the metal connection layer 300 is between the thermal expansion coefficient of the substrate 100 and the thermal expansion coefficient of the metal layer 400.
[0049] As can be seen from the above, the embodiment of the present application can achieve the transition of thermal expansion deformation between the substrate 100 and the metal layer 400 by providing a metal connection layer 300 between the substrate 100 and the metal layer 400, and the metal connection layer 300 has a thermal expansion coefficient between the thermal expansion coefficient of the substrate 100 and the thermal expansion coefficient of the metal layer 400. In other words, the thermal expansion coefficient of the metal connection layer 300 is not much different from the thermal expansion coefficient of the substrate 100, and the thermal expansion coefficient of the metal connection layer 300 is not much different from the thermal expansion coefficient of the metal layer 400. Therefore, when the optical element is in a high temperature environment, the thermal expansion degree of the metal connection layer 300 and the substrate 100 is not much different, and the thermal expansion degree of the metal connection layer 300 and the metal layer 400 is not much different. No large internal stress will be generated between the metal connection layer 300 and the substrate 100 and between the metal connection layer 300 and the metal layer 400, thereby preventing the metal connection layer 300 and the metal layer 400 from rupturing or detaching from the substrate 100.
[0050] It should be noted that the material of the metal connection layer 300 in the embodiment of the present application may include but is not limited to at least one of nickel (Ni), zirconium (Zr), chromium (Cr) and their oxides. Compared with the use of other materials, the embodiment of the present application forms the metal connection layer 300 by using high surface energy materials such as nickel, zirconium, chromium and their oxides, which can ensure that the metal connection layer 300 has a higher surface tension, and then when the metal layer 400 is formed on the surface of the metal connection layer 300, the metal particles can be fully adsorbed on the surface of the metal connection layer 300 to form a dense metal film. As a result, the generation of defects such as pinholes in the metal layer 400 can be greatly reduced, thereby reducing the water vapor and salt spray invading the surface of the metal layer 400 and improving the durability of the metal layer 400. The metal connection layer 300 can be plated on the surface of the substrate 100 by thermal evaporation, physical evaporation, magnetron sputtering or chemical deposition. If the material of the metal connection layer 300 includes metal oxides such as nickel oxide, zirconium dioxide and chromium trioxide, the oxidation degree of high surface energy materials such as nickel (Ni), zirconium (Zr) and chromium (Cr) directly affects the thermal expansion coefficient of the metal connection layer 300. In other words, for the same metal material, the oxidation degree is different, and the thermal expansion coefficient of the metal connection layer 300 formed by it is different. Therefore, in order to limit the thermal expansion coefficient of the metal connection layer 300 within a reasonable range, after the substrate 100 is placed in the vacuum coating chamber, oxygen can be injected into the vacuum coating chamber according to a preset volume flow rate to effectively control the oxidation degree of the above-mentioned high surface energy materials.
[0051] In addition, the material of the metal layer 400 in the embodiment of the present application may include but is not limited to at least one of gold (Au), copper (Cu) and platinum (Pt). The specific material used to form the metal layer 400 can be determined according to the optical properties that the metal layer 400 should have. For example, if the metal layer 400 is to have the property of high reflection of visible light, platinum can be used to form the metal layer 400; if it is to have the property of high reflection of infrared light, copper can be used to form the metal layer 400; if it is to have the property of polarization splitting, gold can be used to form the metal layer 400. The metal layer 400 can also be plated on the surface of the metal connection layer 300 by thermal evaporation, physical evaporation, magnetron sputtering or chemical deposition.
[0052] In some embodiments, the thermal expansion coefficient k of the metal connection layer 300 is o The thermal expansion coefficient k of the metal layer 400 is m Satisfies: 0.1≤k m / k o ≤10. As an example, 0.5≤k m / k o ≤5. For example, k m / k o is 1, 2, 3, 4 or 8. The embodiment of the present application uses the above conditional formula to control the thermal expansion coefficient of the metal connection layer 300 and the thermal expansion coefficient of the metal layer 400, which can not only ensure the high temperature durability of the metal connection layer 300 and the metal layer 400, but also limit the thermal expansion coefficient of the metal connection layer 300 and the metal layer 400 within a reasonable range, ensuring that the thermal expansion coefficient of the metal connection layer 300 is not much different from that of the substrate 100, and at the same time, the thermal expansion coefficient of the metal connection layer 300 is not much different from that of the metal layer 400, thereby reducing the internal stress caused by thermal expansion between the metal connection layer 300 and the substrate 100 and between the metal connection layer 300 and the metal layer 400.
[0053] In some embodiments, the thickness h of the metal connection layer 300 is o , the thickness of the metal layer 400 is h m , the thermal expansion coefficient k of the metal connection layer 300 o The thermal expansion coefficient k of the metal layer 400 is m Satisfy: (|lg(h m / h o )|) / (|ln(k m / k o )|)≤4. As an example, 0.17≤(|lg(h m / h o )|) / (|ln(k m / k o )|)≤3. For example, (|lg(h m / h o )|) / (|ln(k m / k o )|) is 0.5, 1, 1.5, 2 or 2.5. In the embodiment of the present application, by using the above conditional formula to control the thickness and thermal expansion coefficient of the metal connection layer 300 and the thickness and thermal expansion coefficient of the metal layer 400, not only the high temperature durability of the metal connection layer 300 and the metal layer 400 can be improved, but also the thickness of the metal layer 400 and the metal connection layer 300 can be limited within a reasonable range, further reducing the internal stress caused by thermal expansion between the metal connection layer 300 and the substrate 100 and between the metal connection layer 300 and the metal layer 400.
[0054] In some embodiments, the surface tension σ of the metal connection layer 300 is o , the thermal expansion coefficient k of the metal connection layer 300 o The thermal expansion coefficient k of the metal layer 400 is m Satisfies: (lgσ o ) / (|ln(k m / k o )|)≥1.1. As an example, (lgσ o ) / (|ln(k m / k o )|)≥4.5. The embodiment of the present application uses the above-mentioned conditional formula to control the surface tension of the metal connection layer 300 and the thermal expansion coefficients of the metal connection layer 300 and the metal layer 400, so that the metal connection layer 300 has a larger surface tension, so that when the metal layer 400 is formed on the surface of the metal connection layer 300, the metal particles can be fully adsorbed on the surface of the metal connection layer 300 to form a dense metal film, thereby greatly reducing the generation of defects such as pinholes in the metal layer 400, reducing the water vapor and salt spray invading the surface of the metal layer 400, and improving the durability of the metal layer 400.
[0055] In some embodiments, the material of the substrate 100 may include but is not limited to at least one of plastic, metal, glass and composite materials. Compared with the substrate 100 made of other materials, the bonding force between the plastic substrate 100 and the metal connecting layer 300 is slightly weaker. In this case, in order to improve the firmness of the film layer on the surface of the substrate 100, such as Figure 2As shown, the optical element may also include a substrate connection layer 200 located between the substrate 100 and the metal connection layer 300, and the material of the substrate connection layer 200 includes a transition metal oxide. As an example, the above-mentioned transition metal oxide may be niobium oxide (Nb2O5) or tantalum oxide (Ta2O5), etc. The transition metal oxide may be emitted on the surface of the substrate 100 by an ion source, thereby forming the substrate connection layer 200. Under the action of the ion source, both the substrate 100 and the substrate connection layer 200 will generate a trace amount of free radicals, thereby forming a small amount of chemical bonds. As a result, while achieving physical connection between the substrate 100 and the substrate connection layer 200, a chemical connection can also be achieved, thereby increasing the bonding force between the substrate connection layer 200 and the substrate 100, thereby improving the firmness and anti-pulling ability of the substrate connection layer 200 on the surface of the substrate 100.
[0056] In some embodiments, the optical element further includes a dielectric layer 500, which covers the surface of the metal layer 400 away from the metal connection layer 300. The advantages of such a configuration are: on the one hand, the optical properties of the entire optical element, such as reflective performance, can be improved with the help of the dielectric layer 500; on the other hand, since the dielectric layer 500 covers the surface of the metal layer 400 and the chemical properties of the dielectric layer 500 are stable, the dielectric layer 500 can block water vapor and salt fog, reduce the water vapor and salt fog invading the surface of the metal layer 400, and improve the durability of the metal layer 400. It should be noted that the side of the metal layer 400 away from the metal connection layer 300 can form a single dielectric layer 500, or a plurality of dielectric layers 500, and the plurality of dielectric layers 500 are sequentially stacked on one side of the metal layer 400 in a direction away from the metal layer 400, and the materials of the two adjacent dielectric layers 500 are different. When the number of dielectric layers 500 is greater than 3, the two sides of at least one dielectric layer 500 are in contact with the other two dielectric layers 500 of different materials. Of course, at least one dielectric layer 500 may also be in contact with two other dielectric layers 500 of the same material on both sides, which is not limited in the present application. The material of the dielectric layer 500 may include, but is not limited to, at least one of aluminum oxide (Al2O3), silicon oxide (SiO2), titanium oxide (TiO2), niobium oxide (Nb2O5), tantalum oxide (Ta2O5) and magnesium fluoride (MgF2).
[0057] like Figure 6 As shown, the embodiment of the present application also provides a method for preparing an optical element, and the preparation method 1000 includes:
[0058] S100, forming a metal connection layer 300 on the surface of the substrate 100;
[0059] S200 , forming a metal layer 400 on a surface of the metal connection layer 300 away from the substrate 100 ; wherein the thermal expansion coefficient of the metal connection layer 300 is between the thermal expansion coefficient of the substrate 100 and the thermal expansion coefficient of the metal layer 400 .
[0060] In some embodiments, the metal connection layer 300 can be plated on the surface of the substrate 100 by thermal evaporation, physical evaporation, magnetron sputtering or chemical deposition. For example, the formation process of the metal connection layer 300, i.e., step S100, may include: placing the substrate 100 in a vacuum coating chamber, and injecting oxygen into the vacuum coating chamber at a preset volume flow rate, such as 0 to 200 sccm; ionizing the oxygen in the vacuum coating chamber by means of an ion source or ICP (Inductively coupled plasma spectrometer), and bombarding the coating material in the vacuum coating chamber with an electron gun. As a result, the coating material ions and oxygen ions in the vacuum coating chamber combine to undergo an oxidation reaction, and the metal connection layer 300 is formed on the surface of the substrate 100. Among them, the coating material may include, but is not limited to, high surface energy materials such as nickel (Ni), zirconium (Zr) and chromium (Cr). Since the oxidation degree of high surface energy materials such as nickel (Ni), zirconium (Zr) and chromium (Cr) directly affects the thermal expansion coefficient of the metal connection layer 300, in other words, for the same metal material, the oxidation degree is different, and the thermal expansion coefficient of the metal connection layer 300 formed by it is different. Therefore, the embodiment of the present application can effectively control the oxidation degree of the high surface energy material by controlling the amount of oxygen introduced into the vacuum coating chamber, thereby limiting the thermal expansion coefficient of the metal connection layer 300 within a reasonable range, ensuring that the thermal expansion coefficient of the metal connection layer 300 is between the thermal expansion coefficient of the substrate 100 and the thermal expansion coefficient of the metal layer 400. It should be noted that if the material of the metal connection layer 300 is a metal material with high surface energy such as nickel (Ni), zirconium (Zr) or chromium (Cr), the metal connection layer 300 can be directly formed by magnetron sputtering.
[0061] Considering that the bonding force between the plastic substrate 100 and the metal connection layer 300 is slightly poor compared to the substrate 100 prepared by other materials, in order to improve the firmness of the film layer on the surface of the substrate 100, before performing step S100, the preparation method further includes: forming a substrate connection layer 200 on the surface of the substrate 100, and the material of the substrate connection layer 200 includes a transition metal oxide. As an example, the above-mentioned transition metal oxide can be niobium oxide (Nb2O5) or tantalum oxide (Ta2O5). The transition metal oxide can be emitted on the surface of the substrate 100 by an ion source, thereby forming the substrate connection layer 200. Under the action of the ion source, the substrate 100 and the substrate connection layer 200 will generate a trace amount of free radicals, thereby forming a small amount of chemical bonds. As a result, the substrate 100 and the substrate connection layer 200 can achieve a chemical connection while achieving a physical connection, thereby increasing the bonding force between the substrate connection layer 200 and the substrate 100, thereby improving the firmness and anti-pulling ability of the substrate connection layer 200 on the surface of the substrate 100.
[0062] In some embodiments, after executing step S200, the preparation method further includes: forming at least one dielectric layer 500 on the surface of the metal layer 400 away from the metal connection layer 300. The presence of the dielectric layer 500 can not only improve the optical properties of the entire optical element, such as reflective performance, but also block water vapor and salt mist, reduce the water vapor and salt mist invading the surface of the metal layer 400, and improve the durability of the metal layer 400.
[0063] The following is an example of optical elements with different structural forms in the embodiments of the present application:
[0064] Example 1
[0065] like Figure 3 As shown in FIG. 1 , the optical element in this embodiment includes a substrate 100 and a metal connection layer 300, a metal layer 400 and a dielectric layer 500 sequentially stacked on one side of the substrate 100 along the thickness direction of the substrate 100. The substrate 100 is a glass lens, the material of the metal connection layer 300 is nickel (Ni), the material of the metal layer 400 is copper (Cu), and the material of the dielectric layer 500 is silicon oxide (SiO2). As shown in Table 1 below, the thermal expansion coefficient of nickel is 1.3*10 -5 , the thermal expansion coefficient of copper is 1.6*10 -5 The thermal expansion coefficient of glass is 5.8*10 -7 It can be seen that the thermal expansion coefficient of nickel is between the thermal expansion coefficient of copper and the thermal expansion coefficient of glass. In other words, the thermal expansion coefficient of the metal connection layer 300 is between the thermal expansion coefficient of the substrate 100 and the thermal expansion coefficient of the metal layer 400. m / k o =1.23, (|lg(hm / h o )|) / (|ln(k m / k o )|)=1.45,(lgσ o ) / (|ln(k m / k o )|)=15.5; where k m is the thermal expansion coefficient of the metal layer 400, k o is the thermal expansion coefficient of the metal connection layer 300, h o is the thickness of the metal connection layer 300, h m is the thickness of the metal layer 400, σ o is the surface tension of the metal connection layer 300 .
[0066] Table 1 Thermal expansion coefficient and surface tension of various materials
[0067] Material Coefficient of thermal expansion Surface tension (at 1800℃, mN / m) Cu(Copper) <![CDATA[1.6*10 -5 ]]> 1152 Ni(Nickel) <![CDATA[1.3*10 -5 ]]> 1655 Glass <![CDATA[5.8*10 -7 ]]> /
[0068] The preparation method of the optical element includes: forming a nickel layer with a thickness of 50nm, namely, a metal connection layer 300, on the surface of a substrate 100 by a magnetron sputtering method; forming a copper layer with a thickness of 100nm, namely, a metal layer 400, on the surface of the metal connection layer 300 away from the substrate 100 by a physical evaporation method; and forming a silicon oxide layer, namely, a dielectric layer 500, on the surface of the metal layer 400 away from the metal connection layer 300 by a physical evaporation method.
[0069] The optical element in this embodiment was subjected to a temperature test, and the test results showed that the optical element was in a high temperature environment with a humidity of 85% and a temperature of 85°C for 1000 hours without abnormality, and according to the SAEJ2527 standard, the optical element was light aging-resistant and without abnormality after 1000 hours. It can be seen that the film layers of the optical element in the embodiment of the present application are not easy to break or separate from the substrate 100, and the substrate 100 and the metal connection layer 300, as well as the metal layer 400 and the metal connection layer 300 and the dielectric layer 500 have a large bonding force, and are very strong.
[0070] Example 2
[0071] like Figure 4As shown, the structure of the optical element of this embodiment is basically the same as that of the optical element of embodiment 1. The same parts as those of embodiment 1 are not described in detail in this embodiment. The difference lies in that: a substrate connection layer 200 is further provided between the substrate 100 and the metal connection layer 300, and a multi-layer dielectric layer 500 is provided on the side of the metal layer 400 away from the metal connection layer 300. The materials of the dielectric layers 500 on the adjacent two sides are different, and the two sides of the middle dielectric layer 500 are in contact with the other two dielectric layers 500 of the same material. Among them, the substrate 100 is a PC plastic lens, the material of the substrate connection layer 200 is niobium oxide (Nb2O5), the material of the metal connection layer 300 is zirconium dioxide (ZrO2), the material of the metal layer 400 is copper (Cu), the materials of the two adjacent dielectric layers 500 are titanium oxide (TiO2) and silicon oxide (SiO2), respectively, and the dielectric layer 500 directly in contact with the metal layer 400 is a silicon oxide layer. As shown in Table 2 below, the thermal expansion coefficient of zirconium dioxide is 1.1*10 -5 , the thermal expansion coefficient of copper is 1.6*10 -5 The thermal expansion coefficient of PC plastic is 5.5*10 -6 ~1.0*10 -5 It can be seen that the thermal expansion coefficient of zirconium dioxide is between the thermal expansion coefficient of copper and the thermal expansion coefficient of PC plastic. In other words, the thermal expansion coefficient of the metal connection layer 300 is between the thermal expansion coefficient of the substrate 100 and the thermal expansion coefficient of the metal layer 400. m / k o =1.45, (|lg(h m / h o )|) / (|ln(k m / k o )|)=0.80,(lgσ o ) / (|ln(k m / k o )|)=8.46; where k m is the thermal expansion coefficient of the metal layer 400, k o is the thermal expansion coefficient of the metal connection layer 300, h o is the thickness of the metal connection layer 300, h m is the thickness of the metal layer 400, σ o is the surface tension of the metal connection layer 300 .
[0072] Table 2 Thermal expansion coefficient and surface tension of various materials
[0073] Material Coefficient of thermal expansion Surface tension (at 1800℃, mN / m) Cu(Copper) <![CDATA[1.6*10 -5 ]]> 1152 <![CDATA[ZrO2 (Zirconia)]]> <![CDATA[1.1*10 -5 ]]> 1480 PC Plastic <![CDATA[5.5*10 -6 ~1.0*10 -5 ]]> /
[0074] The preparation method of the optical element comprises: placing a substrate 100 in a vacuum coating chamber, forming a niobium oxide layer, namely a substrate connecting layer 200, on the surface of the substrate 100; injecting oxygen into the vacuum coating chamber at a volume flow rate of 100 sccm, and ionizing the oxygen in the vacuum coating chamber by means of an ion source or ICP, and bombarding a zirconium material with an electron gun at the same time, so that zirconium ions and oxygen ions in the vacuum coating chamber are combined to generate an oxidation reaction, and a zirconium dioxide layer with a thickness of 100 nm, namely a metal connecting layer 300, is formed on the surface of the substrate connecting layer 200 away from the substrate 100; forming a copper layer, namely a metal layer 400, with a thickness of 200 nm on the surface of the metal connecting layer 300 away from the substrate connecting layer 200 by a physical evaporation method; and alternately forming a titanium oxide layer and a silicon oxide layer on the surface of the metal layer 400 away from the metal connecting layer 300 by a physical evaporation method.
[0075] The optical element in this embodiment was subjected to a temperature experiment. The experimental results showed that the optical element was in a high temperature environment with a humidity of 85% and a temperature of 85°C for 1000 hours without abnormalities. In addition, according to the SAEJ2527 standard, the optical element was light aging-resistant and had no abnormalities after 1000 hours. It can be seen that the film layers of the optical element in the embodiment of the present application are not prone to cracking or detaching from the substrate 100. In addition, since a multi-layer dielectric layer 500 is formed on the side of the metal layer 400 away from the metal connection layer 300, the minimum reflectivity Rmin of the optical element in this embodiment is not less than 99.5%@1550±30nm.
[0076] Example 3
[0077] like Figure 5 As shown, the structure of the optical element of this embodiment is basically the same as that of the optical element of embodiment 2. The same parts as those of embodiment 2 are not described in detail in this embodiment. The difference lies in that at least one dielectric layer 500 is in contact with two other dielectric layers 500 made of different materials on both sides. Among them, the substrate 100 is a PC plastic lens, the material of the substrate connection layer 200 is tantalum oxide (Ta2O5), the material of the metal connection layer 300 is chromium trioxide (Cr2O3), the material of the metal layer 400 is platinum (Pt), and in the direction away from the metal layer 400, the materials of the four dielectric layers 500 are niobium oxide (Nb2O5), aluminum oxide (Al2O3), niobium oxide (Nb2O5) and magnesium fluoride (MgF2) in sequence. As shown in Table 3 below, the thermal expansion coefficient of chromium trioxide is 1.2*10 -5 The thermal expansion coefficient of platinum is 9*10 -6 The thermal expansion coefficient of PC plastic is 1.3*10 -5 ~5*10 -5It can be seen that the thermal expansion coefficient of chromium trioxide is between the thermal expansion coefficient of platinum and the thermal expansion coefficient of PC plastic. In other words, the thermal expansion coefficient of the metal connection layer 300 is between the thermal expansion coefficient of the substrate 100 and the thermal expansion coefficient of the metal layer 400. m / k o =0.75, (|lg(h m / h o )|) / (|ln(k m / k o )|)=1.82nm,(lgσ o ) / (|ln(k m / k o )|)=11.18; where k m is the thermal expansion coefficient of the metal layer 400, k o is the thermal expansion coefficient of the metal connection layer 300, h o is the thickness of the metal connection layer 300, h m is the thickness of the metal layer 400, σ o is the surface tension of the metal connection layer 300 .
[0078] Table 3 Thermal expansion coefficient and surface tension of various materials
[0079] Material Coefficient of thermal expansion Surface tension (at 1800℃, mN / m) Pt (Platinum) <![CDATA[9*10 -6 ]]> 1720 <![CDATA[Cr2O3 (Chromium(III) oxide)]]> <![CDATA[1.2*10 -5 ]]> 1642 PC Plastic <![CDATA[1.3*10 -5 ~5*10 -5 ]]> /
[0080] The preparation method of the optical element comprises: placing a substrate 100 in a vacuum coating chamber, forming a tantalum oxide layer, namely a substrate connecting layer 200, on the surface of the substrate 100; injecting oxygen into the vacuum coating chamber at a volume flow rate of 60 sccm, and ionizing the oxygen in the vacuum coating chamber by means of an ion source or ICP, and bombarding a chromium material with an electron gun at the same time, so that the chromium ions and oxygen ions in the vacuum coating chamber are combined to generate an oxidation reaction, and a chromium trioxide layer, namely a metal connecting layer 300, with a thickness of 150 nm is formed on the surface of the substrate connecting layer 200 away from the substrate 100; forming a platinum layer, namely a metal layer 400, with a thickness of 500 nm on the surface of the metal connecting layer 300 away from the substrate connecting layer 200 by a physical evaporation method; and sequentially forming a niobium oxide layer, an aluminum oxide layer, a niobium oxide layer and a magnesium fluoride layer on the surface of the metal layer 400 away from the metal connecting layer 300 by a physical evaporation method.
[0081] The optical element in this embodiment was subjected to a temperature experiment. The experimental results showed that the optical element was in a high temperature environment with a humidity of 85% and a temperature of 85°C for 1000 hours without abnormalities. In addition, according to the SAEJ2527 standard, the optical element was light aging-resistant and had no abnormalities after 1000 hours. It can be seen that the film layers of the optical element in the embodiment of the present application are not easy to crack or separate from the substrate 100. In addition, since a plurality of dielectric layers 500 of different materials are formed on the side of the metal layer 400 away from the metal connection layer 300, the optical element in this embodiment can meet the spectroscopic requirements of a specific ratio.
[0082] The above specific implementations do not constitute a limitation on the protection scope of this application. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions and improvements made within the spirit and principles of this application should be included in the protection scope of this application.
Claims
1. An optical element, characterized in that: include: Base material; A metal connection layer covering the surface of the substrate; as well as A metal layer covering the surface of the metal connection layer away from the substrate; Wherein, the thermal expansion coefficient of the metal connection layer is between the thermal expansion coefficient of the substrate and the thermal expansion coefficient of the metal layer.
2. The optical element according to claim 1, wherein The thermal expansion coefficient k of the metal connection layer o The thermal expansion coefficient k of the metal layer m satisfy: 0.1≤k m / k o ≤10。 3. The optical element according to claim 1, wherein The thickness of the metal connection layer h o , the thickness of the metal layer h m , the thermal expansion coefficient k of the metal connection layer o The thermal expansion coefficient k of the metal layer m satisfy: (|lg(h m / h o )|) / (|ln(k m / k o )|)≤4。 4. The optical element according to claim 1, wherein The material of the metal connection layer includes at least one of nickel, zirconium, chromium and oxides thereof.
5. The optical element according to any one of claims 1 to 4, wherein: The surface tension σ of the metal connection layer o , the thermal expansion coefficient k of the metal connection layer o The thermal expansion coefficient k of the metal layer m satisfy: (lgσ o ) / (|ln(k m / k o )|)≥1.1。 6. The optical element according to any one of claims 1 to 4, wherein: The material of the substrate is plastic. The optical element further comprises a substrate connecting layer located between the substrate and the metal connecting layer. The material of the substrate connecting layer comprises transition metal oxide.
7. The optical element according to any one of claims 1 to 4, wherein: The optical element further comprises a dielectric layer, and the dielectric layer covers a surface of the metal layer away from the metal connection layer.
8. The optical element according to claim 7, wherein: The number of the dielectric layers is multiple, and the multiple dielectric layers are sequentially stacked on one side of the metal layer in a direction away from the metal layer, and the materials of two adjacent dielectric layers are different.
9. The optical element according to claim 8, wherein: Two sides of at least one of the dielectric layers are respectively in contact with the other two dielectric layers made of different materials.
10. The optical element according to claim 7, wherein: The material of the dielectric layer includes at least one of aluminum oxide, silicon oxide, titanium oxide, niobium oxide, tantalum oxide and magnesium fluoride.